Greetings team PYBAMM,
I am doing a step charging experiment with pybamm and face numerical issues i.e. Experiment is infeasible: ‘Event exceeded in initial conditions’ error. I apply a step charging protocol with voltage charging for every 5 % SOC till 100 % SOC(fully charged condition). As I cannot directly specify SOC in charging experiment pybamm syntax i use corresponding voltage (i got the Voltage-SOC relationship from a CC-CV charging experiment) as the termination condition. The 0% SOC voltage is 2.85 V and 5% is 3.4 V, 10 % is 3.5 V and it reaches the full cell voltage of 4.2 V at 100 % SOC. when i start from 0% SOC i.e., 2.85 V, my simulation runs but if i start the charging experiment with intermediate values like 15 % SOC (i.e, 3.6 V) then the simulation readily fails with the below error message,
Experiment is infeasible: 'Event exceeded in initial conditions' was
triggered during 'Charge at 25 A until
3.703905097784591 V (1 second period)'.
If i reduce the charging current then I am able to run but i want to use the test specified values. I use version 25.6 with IDAKLU solver. My guess is that it may be due to jump(instantaneous resistance) in voltage as soon as charging event starts and the voltage window from 15 to 20 % SOC (0.1 V) is small as against 0 to 5% SOC(0.6 V). how can i control this. will appreciate any help here. thanks.